Østervold Observatory is a former astronomical observatory in Copenhagen, Denmark owned and operated by the University of Copenhagen. It opened in 1861 as a replacement for the university's old observatory at Rundetårn.
Østervold Observatory
Østervold Observatory
The dome of the observatory
The dome of the observatory seen from Rosenborg Castle Gardens
The Round Tower is a 17th-century tower in Copenhagen, Denmark, one of the many architectural projects of Christian IV of Denmark. Built as an astronomical observatory, it is noted for its equestrian staircase, a 7.5-turn helical corridor leading to the platform at the top, and its views over Copenhagen.
Rundetaarn
Rundetaarn. Illustration from the architect Laurids de Thurah's Hafnia hodierna of 1748.
Cross section of the tower and the church from Thurah's Hafnia Hodierna
The interior of the tower on a drawing by H.G.F. Holm in connection with his proposal to move the tower to a position next to the church